The present invention relates to a planetary transmission having a housing and at least one planetary stage which comprises at least one sun gear which is provided on a sun gear shaft that is rotatably mounted on the housing, at least one planet gear carrier that is rotatably mounted on the housing, at least two planet gear pins which are fastened to the planet gear carrier and on each of which a planet gear is rotatably held, and at least one ring gear fastened non-rotationally within the housing and having an internal toothing and with which the planet gears are in engagement.
Planetary transmissions of this type are known in a variety of designs from the prior art. For the identification of damage to such planetary transmissions, normally condition monitoring systems are used which gather operational data using a wide variety of sensors and enable both a condition diagnosis and also in a broader context, enable an assessment of the remaining service life of components or component groups. The operational data gathered can be, for example, temperatures of the bearings, the oil in the supply and return conduits and of the oil in the transmission sump, oscillation values of components in different spatial axes, acoustic emissions in the kilohertz range, particle sizes and/or particle size distributions in oil streams, rotary speeds of individual components, deformations and/or displacements of components, torques and/or forces acting on components, rotary oscillations or the like, to name only a few examples. The measurement variables acquired by the sensors are normally gathered in a data acquisition computer, whereupon an evaluation takes place either against a trend monitoring of the moving average or against pre-set reference values.
A fundamental problem in condition monitoring of planetary transmissions lies in gathering operational data primarily using locally fixed sensors without difficulty and at low cost. However, a measuring technology-based application of sensors on rotating machine parts is very cost-intensive. For this purpose, expensive radio transmitting systems are required which must transfer both the data and also the energy for the sensors, for which purpose in many cases, dedicated amplifiers or signal pre-processing systems must be arranged on the rotating component. Furthermore, the damage to be identified is influenced by a plurality of factors, so that the number of sensors provided on the rotating component is correspondingly large in order to be able to acquire the different operational data. Against this background, applications of measuring technology on rotating machine parts are currently avoided where possible.